title: Monoclonal antibody HBME-1 reacts with a minor subset of B cells with villous surface and can be useful in the diagnosis of hairy cell leukemia and other indolent lymphoproliferations of villous B lymphocytes.
abstract: The Hector Battifora mesothelial epitope-1 (HBME-1) monoclonal antibody has been generated against human mesothelioma cells and recognizes a biochemically unknown membrane epitope. We have accidentally found that the HBME-1 reacts with scattered lymphocytes showing villous surface in hyperplastic lymphoid tissue. To evaluate its reactivity pattern, we have performed a consecutive immunohistochemical study in nonneoplastic bone marrow and lymphoid samples (n = 40), as well as in malignant lymphoproliferations (n = 427), including hairy cell leukemia (HCL) (n = 72), HCL variant (HCL-v) (n = 13), splenic diffuse red pulp small B cell lymphoma (SDRPL) (n = 8), splenic B cell marginal zone lymphoma (SMZL) (n = 59), and splenic B cell lymphoma/leukemia, not further classifiable on bone marrow morphology (SBCL) (n = 37) cases. The staining pattern of HBME-1 was compared to DBA.44. HBME-1(+) villous lymphocytes were constantly detected in low number in nonneoplastic lymphoid tissues. With multicolor immunofluorescence staining, HBME-1(+) lymphocytes showed a CD20(+)/CD79a(+)/IgM(+) B cell phenotype. In B cell lymphoproliferations of villous lymphocytes, HBME-1 reactivity was demonstrated in 96 % of HCL, 39 % of HCL-v, 50 % of SDRPL, 12 % of SMZL, and 19 % of SBCL cases. Nodal and extranodal marginal zone lymphoma cases were positive in 12 % of the cases. A small minority (4 %) of the other B cell lymphomas and no T cell lymphoma revealed tumor cell reactivity with HBME-1. In conclusion, our study has established that HBME-1 reacts with a minor subset of B lymphocytes and a small proportion of B cell lymphomas, which has not been described previously. We suggest that HBME-1 can be a useful marker in the diagnosis of HCL and other indolent lymphoproliferations of villous B lymphocytes.
authors.affiliation: Laboratory of Tumor Pathology and Molecular Diagnostics, Derkovits fasor 7-11, 6726, Szeged, Hungary, krenacsl@vipmail.hu.
authors.forename: László
authors.initials: L
authors.lastname: Krenács
authors.forename: Judit
authors.initials: J
authors.lastname: Tóth-Lipták
authors.forename: Judit
authors.initials: J
authors.lastname: Demeter
authors.forename: Klára
authors.initials: K
authors.lastname: Piukovics
authors.forename: Zita
authors.initials: Z
authors.lastname: Borbényi
authors.forename: Péter
authors.initials: P
authors.lastname: Gogolák
authors.forename: Eszter
authors.initials: E
authors.lastname: Sári
authors.forename: Enikő
authors.initials: E
authors.lastname: Bagdi
mesh_terms: D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D007943:Leukemia, Hairy Cell / Q000175:diagnosis*; D016393:Lymphoma, B-Cell / Q000175:diagnosis*; D046888:Tissue Array Analysis; D000951:Antigens, Neoplasm
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; C432845:HBME-1 antigen; D000951:Antigens, Neoplasm